Gel coated composite articles are commonly used in a wide variety of applications. Gel coats provide improved weathering characteristics and surface appearance. In some applications, e.g., countertops and bathroom fixtures, the composite article preferably simulates the appearance of natural materials such as granite, marble or other stone. A number of methods are known to produce the simulated stone appearance.
U.S. Pat. No. 5,504,126 described a simulated mineral article comprises a discrete suspended plastic material and a continuous thermoplastic matrix. The plastic material and the thermoplastic matrix are visually distinguishable from each other and each contains a coupling agent. The patent also provides a method of preparing a simulated mineral article which entails preparing a liquid thermoplastic to serve as a matrix and then suspending a plastic material therein. The plastic material is composed of a thermoset plastic made from resin which comprises an acid component having thermoplastic characteristics.
U.S. Pat. No. 5,476,895 describes a sprayable coating composition that is useful for forming a simulated granite surface having high-impact strength, superior hardness and an aesthetically-pleasing look. The coating composition has a gel coat and granules which include thermoplastic and thermoset plastic components. The gel coat and granules are visually differentiable from each other, substantially immiscible and substantially isopycnic in density. The composition, when combined with a hardener, may be sprayed into a mold and backed with fiber glass, plastic or other suitable resin to form a panel or similar structure, or may be directly applied to a surface to provide a simulated-granite appearance.
Japan patent 02-102156 described a hot press molding resin composition to improve transparency and gloss by hot-pressing a molding composition containing an unsaturated polyester resin, curing agent, cured product powder of an unsaturated polyester resin, specific inorganic filler and mold releasing agent.
Japan patent 06-25539 described colored resin particles for decorated moldings. The colored resin particles were obtained by dissolving the thermoplastic resin, in uncured thermosetting resin. Filler and pigment were then added into the resin solution and the resin solution was cured and crushed into small pieces.